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A radioactive sample has a half-life of $T_{1/2} = 20$ days. What fraction of the original sample will remain undecayed after $t = 100$ days?
- A.$1/8$
- B.$1/16$
- C.$1/32$
- D.$1/64$
Show correct answer & step-by-step solution
Correct answer: C — $1/32$
Solution
The number of half-lives elapsed is . The remaining fraction is given by , which equals .
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